Paolo Verderio

HER2 Expression in Breast Cancer Cells Is Downregulated Upon Active Targeting by Antibody-Engineered Multifunctional Nanoparticles in Mice

Subcellular destiny of targeted nanoparticles in cancer cells within living organisms is still an open matter of debate. By in vivo and ex vivo experiments on tumor-bearing mice treated with antibody-engineered magnetofluorescent nanocrystals, in which we combined fluorescence imaging, magnetic relaxation, and trasmission electron microscopy approaches, we provide evidence that nanoparticles are effectively delivered to the tumor by active targeting. These nanocrystals were demonstrated to enable contrast enhancement of the tumor in magnetic resonance imaging. In addition, we were able to discriminate between the fate of the organic corona and the metallic core upon cell internalization. Accurate immunohistochemical analysis confirmed that hybrid nanoparticle endocytosis is mediated by the complex formation with HER2 receptor, leading to a substantial downregulation of HER2 protein expression on the cell surface. These results provide a direct insight into the pathway of internalization and degradation of targeted hybrid nanoparticles in cancer cells in vivo and suggest a potential application of this immunotheranostic nanoagent in neoadjuvant therapy of cancer.

Prognostic and predictive value of tumour angiogenesis in ovarian carcinomas

Experimental studies suggest that angiogenesis plays an important role in the pathogenesis of ascites and progression of ovarian cancer. To evaluate the association of intratumoral microvessel density (IMD) with the conventional clinicopathologic features and to determine the capability of these factors in predicting responsiveness to platinum‐based chemotherapy and overall survival (OS) we studied 112 ovarian carcinomas. IMD was determined using the anti‐CD31 antibody and immunocytochemistry. In the entire series, we correlated IMD with the other features. In the subgroup of patients with FIGO stage III‐IV (60 cases), we correlated the factors studied, determined prior of treatment, with response to therapy and prognosis.

Evaluation of SNPs in miR-146a, miR196a2 and miR-499 as low-penetrance alleles in German and Italian familial breast cancer cases

Recently, the SNPs rs11614913 in hsa‐mir‐196a2 and rs3746444 in hsa‐mir‐499 were reported to be associated with increased breast cancer risk, and the SNP rs2910164 in hsa‐mir‐146a was shown to have an effect on age of breast cancer diagnosis. In order to further investigate the effect of these SNPs, we genotyped a total of 1894 breast cancer cases negative for disease‐causing mutations or unclassified variants in BRCA1 and BRCA2, and 2760 controls from Germany and Italy. We compared the genotype and allele frequencies of rs2910164, rs11614913 and rs3746444 in cases versus controls of the German and Italian series, and of the two series combined; we also investigated the effect of the three SNPs on age at breast cancer diagnosis. None of the performed analyses showed statistically significant results. In conclusion, our data suggested lack of association between SNPs rs2910164, rs11614913 and rs3746444 and breast cancer risk, or age at breast cancer onset.

Prognostic value of intratumoral microvessel density, a measure of tumor angiogenesis, in node-negative breast carcinoma — results of a multiparametric study

SummaryIn the present study we update previous results on the prognostic value of intratumoral microvessel density (IMD), determined immunocytochemically using the monoclonal antibody CD-31 and a standard streptavidin-immunoperoxidase technique, published in theJ Clin Oncol 12:454–466, 1994. This study was undertaken in those 211 node-negative breast cancer (NNBC) cases of that series of which we had pathological material available to determine all the prognostic indicators. The median period of follow-up has been extended to 78 and 80 months for relapse-free survival (RFS) and overall survival (OS), respectively, and new biological indicators (i.e. Ki-67 labeling and 67 kDa laminin receptor expression) were included in the analysis.The main results obtained are:i) a confirmation that IMD is not associated with the other biological markers studied, i.e. expression of p53 protein, c-erbB-2 protein, 67 kDa laminin receptor, and cell kinetics; IMD was weakly associated only with histological grade (p=0.053);ii) IMD remains a highly significant prognostic factor for RFS and OS (p<0.0001 and p=0.018, respectively) in univariate analysis;iii) in multivariate analysis on RFS, IMD (likelihood ratio test (LRT)=30.16; p<0.0001), 67 kDa laminin receptor (LRT=9.80; p=0.0017), the IMD/67 kDa laminin receptor interaction (LRT=8.62; p=0.0033), tumor size (LRT=8.56; p=0.0034), and p53 protein (LRT=4.96; p=0.025) are significant and independent prognostic indicators. For OS, only tumor size (LRT=8.34; p=0.0038), menopausal status (LRT=5.16; p=0.023), p53 protein (LRT=4.37; p=0.036), and IMD (LRT=4.05; p=0.044) retain a significant and independent prognostic value.The results of this study confirm the prognostic importance on RFS of the variables previously tested, but not of peritumoral lymphatic vessel invasion. A novel finding is that 67 kDa laminin receptor and the IMD/67 kDa laminin receptor interaction are also significant and independent variables. For OS, the results confirm that both IMD and tumor size are significant and independent variables. With prolonged follow-up the novel finding that emerges is the prognostic importance of menopausal status and p53 protein.This new information could be useful for a more accurate selection of high-risk NNBC patients who require careful follow-up and may benefit from adjuvant therapy.

Short, full-dose adjuvant chemotherapy in high-risk adult soft tissue sarcomas: A randomized clinical trial from the Italian Sarcoma Group and the Spanish Sarcoma Group

PURPOSE A previous randomized clinical trial by the Italian Sarcoma Group (ISG) had shown a survival benefit of adjuvant chemotherapy (CT) in high-risk extremity soft tissue sarcoma (STS). However, the dose-intensity of the last two cycles was suboptimal. We then undertook a multicentric international phase III study to compare three and five cycles of the same CT. PATIENTS AND METHODS Patients were randomly assigned either to receive three cycles of preoperative CT with epirubicin 120 mg/m(2) and ifosfamide 9 g/m(2) and granulocyte colony-stimulating factor (arm A) or to receive the same three cycles of preoperative CT followed by two further cycles of postoperative CT (arm B). Noninferiority of the primary end point, overall survival (OS), was assessed by the CI of the hazard ratio (HR; arm A/arm B) obtained from the Cox model. RESULTS Between January 2002 and April 2007, 328 patients were recruited (164 patients in each arm). At a median follow-up of 63 months (interquartile range, 49 to 77 months), 100 deaths were recorded, 49 in arm A and 51 in arm B. Five-year OS probability was 0.70 for the entire group of patients (0.68 in arm A and 0.71 in arm B). The HR of arm A versus arm B was 1.00 (90% CI, 0.72 to 1.39). CONCLUSION In this population of patients with high-risk localized STS, three cycles of full-dose preoperative CT were not inferior to five cycles. The outcome compares favorably with the expected survival of patients with high-risk STS and was superimposable on the CT arm of the previous ISG trial.

miRNA Profiling in Colorectal Cancer Highlights miR-1 Involvement in MET-Dependent Proliferation

Altered expression of miRNAs is associated with development and progression of various human cancers by regulating the translation of oncogenes and tumor suppressor genes. In colorectal cancer, these regulators complement the Vogelstein multistep model of pathogenesis and have the potential of becoming a novel class of tumor biomarkers and therapeutic targets. Using quantitative real-time PCR, we measured the expression of 621 mature miRNAs in 40 colorectal cancers and their paired normal tissues and identified 23 significantly deregulated miRNAs. We subsequently evaluated their association with clinical characteristics of the samples and presence of alterations in the molecular markers of colorectal cancer progression. Expression levels of miR-31 were correlated with CA19-9 and miR-18a, miR-21, and miR-31 were associated with mutations in APC gene. To investigate the downstream regulation of the differentially expressed miRNAs identified, we integrated putative mRNA target predictions with the results of a meta-analysis of seven public gene expression datasets of normal and tumor samples of colorectal cancer patients. Many of the colorectal cancer deregulated miRNAs computationally mapped to targets involved in pathways related to progression. Here one promising candidate pair (miR-1 and MET) was studied and functionally validated. We show that miR-1 can have a tumor suppressor function in colorectal cancer by directly downregulating MET oncogene both at RNA and protein level and that reexpression of miR-1 leads to MET-driven reduction of cell proliferation and motility, identifying the miR-1 downmodulation as one of the events that could enhance colorectal cancer progression. Mol Cancer Res; 10(4); 504–15. ©2012 AACR.

Circulating miR-378 in plasma: a reliable, haemolysis-independent biomarker for colorectal cancer

Background:Plasma circulating tumour-specific microRNAs (miRNAs) are promising biomarkers of tumour presence and recurrence, especially for diseases whose best chance of successful treatment requires early diagnosis and timely surgery of an already malignant but not yet invasive tumour, such as colorectal cancer (CRC).Methods:Expression levels of miRNAs previously found to be differently expressed in tumour vs normal colon tissues were investigated by quantitative real-time PCR in plasma from CRC patients and from healthy donors and confirmed in independent case control series. The validated miRNAs were also measured after surgery. Analyses were repeated on the subsets of haemolysis-free samples.Results:We identified four miRNAs differently expressed between the compared groups, two (miR-21 and miR-378) of which were validated. miR-378 expression decreased in non-relapsed patients 4–6 months after surgery and miR-378 ability to discriminate CRC patients from healthy individuals was not influenced by haemolysis levels of plasma samples.Conclusion:The miRNA analysis on plasma samples represents a useful non-invasive tool to assess CRC presence as well as tumour-free status at follow-up. Plasma levels of miR-378 could be used to discriminate CRC patients from healthy individuals, irrespective of the level of haemoglobin of plasma samples.

Single-domain protein A-engineered magnetic nanoparticles: toward a universal strategy to site-specific labeling of antibodies for targeted detection of tumor cells

Highly monodisperse magnetite nanocrystals (MNC) were synthesized in organic media and transferred to the water phase by ultrasound-assisted ligand exchange with an iminodiacetic phosphonate. The resulting biocompatible magnetic nanoparticles were characterized by transmission electron microscopy, dynamic light scattering, and magnetorelaxometry, indicating that this method allowed us to obtain stable particle dispersions with narrow size distribution and unusually high magnetic resonance T(2) contrast power. These nanoparticles were conjugated to a newly designed recombinant monodomain protein A variant, which exhibited a convincingly strong affinity for human and rabbit IgG molecules. Owing to the nature of antibody-protein A binding, tight antibody immobilization occurred through the Fc fragment thus taking full advantage of the targeting potential of bound IgGs. If necessary, monoclonal antibodies could be removed under controlled conditions regenerating the original IgG-conjugatable MNC. As a proof of concept of the utility of our paramagnetic labeling system of human IgGs for biomedical applications, anti-HER-2 monoclonal antibody trastuzumab was immobilized on hybrid MNC (TMNC). TMNC were assessed by immunoprecipitation assay and confocal microscopy effected on HER-2-overexpressing MCF-7 breast cancer cells, demonstrating excellent recognition capability and selectivity for the target membrane receptor.

Site‐Specific Conjugation of ScFvs Antibodies to Nanoparticles by Bioorthogonal Strain‐Promoted Alkyne–Nitrone Cycloaddition

Particularly suitable: An N-terminal serine mutant of anti-HER2 scFv antibody was conjugated to polymer-coated magnetofluorescent nanoparticles by strain-promoted alkyne-nitrone cycloaddition. The resulting nanoparticles (see scheme) proved effective in targeting and labeling HER2-positive breast cancer cells.

Tumor response assessment by modified Choi criteria in localized high-risk soft tissue sarcoma treated with chemotherapy.

The objective of this study was to compare the prognostic relevance of Response Evaluation Criteria in Solid Tumors (RECIST) versus Choi criteria for the assessment of response in patients with high‐risk soft tissue sarcoma of the extremities or trunk wall who received preoperative chemotherapy with or without radiotherapy in a phase 3 trial.